Aeroplane map device



Aug. 22, 1933. D. NORVELL 1,923,113

AEROPLANE MAP DEVICE Filed Feb. 27, 19:50 4 Sheets-Sheet 1 f M T flatid. H [Van ell Aug. 22, I933.

Filed Feb. 27, 1930 4 Sheets-Sheet 2 Aug. 22, D NORVELL 1,923,].

AEROPLANE MAP DEVICE Filed Feb. 27, 1930 4 Sheets-Sheet 3 22, 1933- D.H. NORVELL 1,923,113

AEROPLANE MAP DEVICE Filed Feb. 27, 1930 4 Sheets-Sheet 4 49 pal id HJ/OJ'WZZ.

Patented Aug. 22, 1933 UNITED STATES "PATENT LoFFicE 1 Claim.

This invention relates to a map device primarily adapted for use onaeroplanes to plot and ascertain the route. I

It is aimed to provide an exceedingly compact construction wherein mapsof the roll strip type may be accommodated and used and wherein largermaps of the folded sheet type may also be accommodated and used. 1

Another object is to provide a novel construc tion which may be equippedwith protractor means. r

A further object is to provide a novel construction wherein the partsare extensible for coaction with the folded sheet map and wherein oneprotractor construction may be thrown into or out of operative positionfor'coaction therewith.

The more specific objects and advantages will become apparent from aconsideration of the description following taken in connection withaccompanying 3 drawings illustrating an operative embodiment.

In said drawingsz- Figure 1 is a plan view of the device, the supportingwalls for a sheet map being shown extended in dotted lines,

Figure 2 is a central longitudinal sectional view through the device ofFigure 1,

Figures 3, 4 and 5 are cross sectional views taken on the lines 3-3, 4-4and 55, respectively, of Figure 2,

Figure 6 is a side elevation of the device showing the auxiliaryprotractor in place, and

Figure 7 is a plan view of the device showing the auxiliary protractorin place.

7 Referring specifically to the drawings, the device embodies a suitablecasing such as the rectangular one shown at 10. Extending rearwardlyfrom the casing are ears ll which have serrated plates 12 thereonadapted to engage serrated plates 13, and be detachably connectedthereto as by means of bolts 14. The plates 13 by means of arms 15 areadapted to be connected to the instrument board of an aeroplane. Theserrations on the plates 12 and 13 enable disposition of the casing 10at any desiredangle.

A suitable clasp device A is carried on the casing adjacent the ears l1and is used for holding sheet maps in folded condition. This clasp meanscomprises attaching arms 16 and pressure arms 17 connected thereto bymeans of coils 18. The pressure arms 17 at their lower ends engage thecasing 10 and adjacent the same are connected by a transverse rod 18from which a knob 19 extends. v It will be understood that themaps areplaced between the arms 1'7 and rod 18 and the casing 10 and areresiliently held against the latter. 1 v Y 'Rotatable within the-casing10 adjacent the opposite ends thereof are spools or drums'20 forinstance having wooden spindles 21 and metal flanges or end disks 22suitably fastened thereto. Extending outwardly from the side walls ofthe casing 10 alined with the members 21 are housings 23in which clutchrods 24 are slidably and rotatably mounted. Such clutch rods 24 haveclutch heads 25 detachably engaging suitable clutch means at the ends ofthe spools 20. Such clutch means are held normally in engagement throughthe'action of an expansive coil spring 26 surrounding the rods 24 andabutting the housings 23 and stops 2'? on such rods.

The rods 24 are adapted to be retracted by engagement with knurledoperating knobs 28, in

order to engage and'disengage the spools 20 so that they maybe removedor'mounted. It will 5 be noted that the operating devices for the spoolsare located at each end thereof so that the operator may manipulate thesame either with the right or left hand.

Removably engaged with the shaft or cores 21 of the spools are the endsof a map of suitable sheet material 30, the map being adapted to bewound onto one spool as it is paid off the other and vice versa. Suchmap passes over idler rollers 31 and also over the platen 32 which isremovable and detachably held in place by the engagement of a springclasp 33 with a cross bolt 34, additional means such as'lugs or rests 35being provided on the casing 10 for engagement by the platen on oppositesides of the bolt 34.

Spools containing maps such as 30 maybe detachably carried Within thecasing 10, the ends of their hubs being engageable bylugs 36 which formpart of spring arms 37 fastened as at 38 to the side walls of saidcasing 10.

The invention has a suitable protractor arranged over the platen 32 andin cooperating rela- 7 tion to the map 30. The map as will be understoodcontains means to delineate the route, the degree of travel, the landingfields, towns, altitude marks, mountain ranges to be crossed, distancesbetween points or routes and the like. A protractor is shown at 39 beingdelineated for example on a transparent sheet 40 of celluloid or othermaterial fastened as at 41 to the casing 10. Movable over the protractor39 and coacting with the indications thereof is a pointer or indicator42 pivoted to the sheet at 43. A clasp 44 may be carried by the sheet 40for engagement by the indicator 42 when the same is not in use.

It will be realized that the rolls or spools 20 accommodate the use ofspecial maps. In order to permit the use of larger maps and in factpractically any map, means are provided whereby the surface of thecasing may be extended and used as a support for such a map. To thisend, map

supporting wings 45 are hinged to the casing at 46 v and have variousopenings 47 therethrough, permitting such wings to be folded flatagainst the sides and one end of the casing, with the adjacent partsextending through the openings 47. Latches 48 of any suitable spring orother type are adapted to enter openings 49 in the wings and engage thesame to normally hold them against opening. The fit at the hinges 46 isrelatively tight so that the wings will remain in the open position ofthemselves, that is the position shown in dotted lines in Figure 1 andin full lines in Figure '7.

To coact with maps supported in the casing and extended wings 45, alarger protractor than that disclosed at 39 is necessary. To this end,such a large protractor is provided at 50, constituting for exampleanintegral part ofa celluloid or transparent sheet 51. Such sheet 51 hasa pointer or indicator 52 pivoted at the'center thereof and which isextended as shown at 53 to point directly to a position on the map, 54designating a handle or knob for convenience in moving the pointer 52.The sheet 51 is fastened to a bracket 55 as by means of screws 56 andsuch bracket carries a clasp 5'7 engageable by'the pointer 52 so as tonormally hold the latter inactive. The bracket 55 has attaching arms 58and a series of serrated portions 59 thereon, adapted for selectiveengagement with serrated plates 60 mounted on extension members 61pivoted as at 62 to the casing 10. Bolts 63 pass through the members 59and extensions 61 and adjustably secure the parts in place. It will berealized that the sheet 51 may be swung from the axis 63 to a positionwhich will not obscure the other protractor and map when the largeprotractor is not in use. It will be understood that when the sheet 51and bracket 55 are not used, that the extensions 61 may be folded acrossthe casing 10 for compactness. The strip map is usually four inchesWide, the route of travel is in the longitudinal middle thereof, and ifthe map be made on a scale of fifteen miles to the inch there would be aspan of thirty miles in each side of the route. The map will show allavailable landing ports or fields within the area covered by the map.Should the aeroplane experience adverse weather conditions, ormechanical difliculties, making it necessary to make a forced landing,the navigator may select the nearest available landing port or field asshown on the map, and by moving the hand 42 to point in the direction ofsuch landing the hand will indicate on the dial 39 the number of degreesoff its course that the plane will have to proceed to make the landing.

Various changes may be resorted to provided they fall within the spiritand scope of the invention. 4

I claim as my invention:

A. device of the class described comprising a casing, extensible meanson the casing to support a map, a sheet of material provided with aprotractor mounted on the casing in oifset relation thereto and incooperative relation with the map, a bracket supporting said sheet andadjustably securing it to the casing whereby it may be moved into andout of operative position over said map, said bracket having arms,serrated portions on said arms, extensions on said casing, saidextensions having serrated portions selectively engageable with theserrated portions of the arms, and bolts to secure engaged serratedportions together.

' DAVID H. NORVELL.

